Well cementing device



June 18, 1940. c. E. BURT 2,204,653

WELL CEMENTING DEVICE Filed Dec. 12, less IN VEN TOR.

ATTORNEY mama June is, 1949 STATES WELL CEMENTING DEVICE I Clarence E. Burt, Los Angeles, Calif., assignor to Baker Oil Tools, Inc.,

Huntington Park, Calih,

a corporation of California Application December 12, 1938, Serial No. 245,241

6 Claims.

This invention relates to tools and equipment utilized during the drilling of oil wells.

It is the principal object of my present invention to provide a simple and eiiicient apparatus for use in cementing operations in properly forming a cement plug in an open well bore a proper distance below the lower. terminal of the well casing. y

In practicing my invention, I provide a tubular member such as acasing shoe for attachment to the lower end of a well casing. I also provide a tail pipe or tube which is comparatively small in diameter with respect to the diameter of the well casing and which is connected at its upper end to the shoe by means of a connector means which also serves as a guide for the lower end of the casing. Ihis tail pipe or tube extends downwardly a considerable distance and is provided with a nozzle at its lower end; the nozzle; the tube and the connector means being preferably of drillablc material. When the casing is lowcred into position in the well bore, it is dcsir able to form a comparatively long solid cement plug in the bore directly below the same. By means of the arrangement that I have just described, cement may be discharged at the lower end of the tail pipe to form this plug and after the cement has set and it is desired to proceed with the drilling, the connector means, the tail pipe and the plug may be readily drilled through.

One form which the invention may assume is exemplified in the Iollowingdescription and illustrated by way of example in the accompanying drawing, in which: i

Fig. 1 is a view in elevation of an apparatus embodying the preferred form of my invention and showing it in position in a well bore.

Fig. 2 is a central vertical sectional view through my apparatus disclosing its construction. 40 Fig. 3 is a view similar to Fig. 1 with the exception that a difierent type of nozzle is provided at the lower end of the tail pipe. 7

Referring more particularly to the accompanying drawing, it] indicates a tubular member, such as a casing shoe, which is adapted to be connected to the lower end of a well casing, as in standard practice. Cast or otherwise secured into the casing shoe it! is a cementitious plug ii, the lower end of which is rounded as at it so as to be guide-shaped and thereby guide the lower end of the casing past the joints in the casing.

Fixed centrally within this concrete or cemerrtitious plug it is a concentrically located sleeve I t which is interiorly threaded at its lower end to 55 receive a tail pipe or tube It. The upper end of this tube 65 is threaded into the sleeve M as illustrated so as to seure it: thereto and thereby attach it to the casing shoe ill.- The length of the tail pipe It may be such as desired-or such as is necessary .to form a cement plug of the desired 5 lengthin the well bore.

It will be noticed that the interior of the casing shoe it is provided with a valve chamber I6 and a back-pressure valve ll so that the casing may be floated into place in the Well bore. Likewise, 10 the provision of the back-pressure valve il enables cement or fluid to be discharged downwardly through the casing'shoe it and into the tail pipe it, but prevents the back flow of fluid up- Wardly into the well casing through the casing 1:; shoe it;

At the lower end of the tail pipe it is a nozzle iii, and in the present instance I have shown two types of nozzles. In Figs. 1 and 2 I have shown a whirler type of nozzle which is secured in the 2 lower end of the imperforate tail pipe. This nozz e is formed with spirally arranged passageways lt so that cement or other fluid discharged downwardly through the tail pipe will be caused to swirl as it is ejected. In cementing operations, 25 this has a particular'advantage in that it evenly distributes the cement slurry around the bore and prevents channeling of the cement so that a proper cement plug will be formed.

In Fig. 3 I'have shown the tail pipe as having a nozzle which is provided with aplurality of radially directed ports ill.

I prefer that the concrete plug l i, the tail pipe iii and the nozzle it be formed of drillable material. For example, the connector means or plug it may be'formed of concrete, bakelite or drillable aluminum, if so desired, and I prefer that the tail pipe it be .Iormed of a suitable aluminum alloy which is easily drilled up. The nozzle iii may be formed of like material. 4

' In Fig. 2 I have shown the casing shoe as pro-'- vided with a back-pressure valve i'l However, this is not necessary as a plain guide type of shoe may be employed in lieu thereof.

In operation of the device, it is constructed as illustrated and described and the casing is lowered into the well bore. Circulation may be maintained downwardly through the casing and through the tail pipe during the loweringation, and after the casing has'been positioned, so cement may be pumped downwardly through the casing andit will pass through the casing shoe it into the tail pipe it and be discharged through the nozzle it. In the event a nozzle such as is illustrated in as Figs. 1 and 21s provided, the cement will be ejected in a circular or spiral fashion to insure equal distribution of the cement in the bore and thereby prevent channeling. If the nozzle provided is the type shown in Fig. 3, the cement will be ejected radially from all sides of the tail pipe so that equal distribution will be provided.

After the cementing operation is complete, a

' solid cementitious plug will be formed in the bore below and surrounding the casing shoe. It

is desirable in some localities that this plug be solid for a distance at least fifteen feet below the casing and in such instances the tail pipe is of a length enabling this to be accomplished. The tail pipe 95 will be incorporated in this plug as it will be cemented solidly therein and likewise its'interior will be filled with cement.

If it is desired to drill through the cement plug,

the drill may readily advance through the casing shoe, drilling up the connecting member l I and may advance further by drilling up the cement and the tail pipe and the nozzle at the lower end of the latter.

While I have shown the preferred form of.

casing, an elongated tube of a diameter consider-- ably less than the cylindrical member to extend coaxially from the lower end thereof, and means secured to the cylindrical member and tube to connect the same and to close the annular space between the exterior of the tube and the cylindrical member, a whirler nozzle at the lower extremity of said tube.

2. In combination, a cylindrical member adapted be connected to the lower end .of a. well casing, an elongated tube of a diameter considerably less than the cylindrical member toextend coaxially from the lower end thereof, means secured to the cylindrical inemberand tube to connect the same and to close the annular space between the exterior of the tube and the cylindrical member, a nozzle at the lower end of the tube, said nozzle having discharge ports extending downwardly in spiral fashion.

3. In combination with a cylindrical member adapted to be connected to the lower end of a well casing, an elongated tail pipe of a diameter considerably less than the cylindrical member to extend coaxially from the lower end thereof, a guide member secured to the cylindrical member and to which said tail pipe is secured, said guide member closing the annular space between the interior of the tail pipe and the cylindrical member, a nozzle at the lower end of said tail pipe, said nozzle having a plurality of discharge passageway formed downwardly therethrough, said passageways being spirally formed so as to tend to discharge the fluid in a whirling fashion.

4. In combination with a cylindrical member adapted to be connected to the lower end of a well casing, an elongated tail pipe of a diameter considerably less than the cylindrical member to extend coaxially from the lower end thereof, a. guide member secured to the cylindrical member and to which said tail pipe is secured, said guide member closing the annular space between the interior of the tail pipe and the cylindrical member, a nozzle at the lower end of said tail, pipe, said nozzle having a plurality of discharge passageways formed downwardly therethrough,

said passageways being spirally formed so as to tend to discharge the fluid in a whirling fashion,

said guide means, said tail pipe and said nozzle being formed of drillable material.

5. In combination, a'casing shoe adapted to be secured to the lower end of a well casing, an

elongated tail pipe of a diameter considerably less than the casing shoe to be suspended coaxially therefrom, a concrete plug cast in said casing shoe and-having a guide-shaped nose extending from the lower end thereof, a sleeve secured within said concrete nose, a threaded connection between said sleeve and said tail pipe, and a fluid discharging nozzle formed at the lower end of said tail pipe- 6. In combination, a well casing having a drillable reducer at its lower end, an elongated drillable tube or extension of a smaller diameter than the casing and secured to the drillable reducer and suspended from the casing thereby, a float valve in the drillable reducer above said tube, and cementing outlets in said tube at a substantial distance below the lower end of the well casing.

CLARENCE E. BURT. 

